Carnivorous Plants/Transcript
Transcript A robot, Moby, is watering a Venus fly trap. A housefly flies around the plant. Text reads: The Mysteries of Life with Tim and Moby. The fly goes around a sundew plant before flying into the Venus fly trap, which then snaps shut. A man, Tim, approaches. TIM: Hey, Moby, how’s your creepy plant collection coming along? Moby looks annoyed and hands Tim a letter, which Tim reads. MOBY: Beep! TIM: Dear Tim and Moby, Do Venus flytraps make their own food? From, Braves Boy. Well, uh...yes and no...Like any plant, some of their nutrition comes from substances found in soil. A cross-section of a patch of dirt with a Venus fly trap growing in it is shown. Arrows point from the soil to its roots. TIM: And some of it comes from photosynthesis, the way that plants convert sunlight, water, and carbon dioxide into sugar. A large leaf is shown. Sunlight falls from the sky onto the leaf. TIM: But most carnivorous plants live in extreme environments where the soil just isn’t that great. Like most meat-eating plants, the Venus flytrap lives in swampy areas. Now, there’s plenty of light and water there, but the soil doesn’t have all the nutrients that it needs—especially nitrogen. So it makes up for this thin soil by gathering nutrients from insects and other small animals! A close-up of the Venus fly trap’s roots is shown, along with a close-up of nitrogen particles in the dirt. The Venus fly trap is shown again with a fly inside its mouth. MOBY: Beep? TIM: Oh, carnivorous just means meat-eating. There are lots of different carnivorous plant species—most of which Moby seems to own. And, as you can see from his collection, they’ve evolved a lot of different ways to do it! MOBY: Beep? Moby’s collection of carnivorous plants is shown in a row on the table. There are a butterwort, a pitcher plant, a dewy pine, and a bladderwort. TIM: One of the simplest is the pitfall trap, a cup-shaped growth with liquid inside. This pitcher plant is a classic pitfall. It lures bugs in with the promise of sweet, delicious nectar. But once they come in, they drown in the stuff inside. Tim stands next to the pitcher plant. It has a broad stem that curves downward and supports a deep cup-shaped growth with a lid-like flap on top. A fly flies into the liquid in the cup-shaped growth and sinks. TIM: The lobster pot trap is pretty basic, too. Like pitfall plants, lobster pots are passive—they just hang out waiting for insects to enter. Inward-pointing hairs force the bug to keep crawling in one direction, until it gets to a sort of stomach, where it’s digested. A cross-section of a planted lobster pot trap is shown. It has a long, thin stem with a yellow flower on top and a cluster of long leaves at its base. Each of its roots is a two-pronged fork with a bulb-shaped pocket above the prongs. A beetle crawls into one of the prongs, which is lined with hairs that point inward. It continues up the root until it reaches the pocket, where it dissolves. Tim stands next to the dewy pine plant. TIM: This dewy pine plant... MOBY: Beep! TIM: Randolph? You named it Randolph? All right, well, Randolph the dewy pine plant is a good example of a flypaper trap. These sticky beads smell delicious to insects. But once they land there, they’re stuck! Pretty soon, the plant absorbs the nutrients from their decaying bodies. The dewy pine plant has long leaves that coil up at the top. The leaves are covered in little hairs with round beads on the end. A fly lands on the plant and gets stuck. Tim stands next to the sundew plant. TIM: Some flypaper plants are active—they move to help capture their prey. This sundew plant… MOBY: Beep! Moby sticks a label into the plant’s pot. Text reads: Eric. Tim sighs. TIM: Eric the sundew plant has sticky tentacles to trap its food, but it also has special motion sensors. When dinner triggers the sensors, the sundew closes up around it, making escape even more difficult. The sundew plant has narrow stems with long bulb-shaped structures at the top. These structures are covered in slightly longer hairs with round beads on the end. A fly lands on one of the bulb shapes, which then curls down around the fly, trapping it. MOBY: Beep? TIM: No, it actually doesn’t have muscles. Carnivorous plants have cells that move in response to touch. When a bug touches Eric the sundew, a chemical reaction starts. The cells on one side of its tentacles expand really fast, causing them to bend. A close-up shows the beaded hairs on the sundew plant. A dragonfly lands on the plant and the hairs bend, keeping the dragonfly in place. TIM: Other traps move by changing the water pressure within their cells. When this Venus fly trap senses a bug in its...well, in its “mouth,” the cells in its leaves swell with extra water, making the leaves snap shut. Pretty cool, huh? The Venus fly trap’s trap is shown. The trap is shaped like a round open coin purse lined on the outside with long toothlike structures. The cells inside of the “mouth” are shown in a separate window. When a fly lands in the trap, the cells get bigger and the trap closes. Tim stands next to the bladderwort. TIM: This one has a really amazing active trap called a bladder trap. When its sensors detect motion, special pumps suck water into the plant. Any small creatures nearby get vacuumed in, too. The bladderwort is sitting in a bowl of water. A close-up of its roots is shown. The roots are long, thin tendrils with little bulbs attached. An insect swimming in the water is sucked into the end of one of the tendrils and into the attached bulb. MOBY: Beep? TIM: Well, all these plants live mainly on insects, but they can eat small animals, too, like mice or frogs. Speaking of which, have you seen Hoppy? An image of a mouse and then of a frog is shown. MOBY: Beep. Beep. Moby shakes his head. TIM: What was that? MOBY: Beep. Beep! Moby shrugs. He has a hand on his moving Venus fly trap, where the ribbiting is coming from. TIM: Well, it didn’t sound like the wind. Category:BrainPOP Science Transcripts Category:BrainPOP Transcripts